Many industries require signs and labels to efficiently and effectively identify equipment, product flow through processes, and warn of potential hazards to workers. Signs and labels used in this manner must maintain utility—both legibility and permanence—throughout a reasonable lifespan. Replacement of this type of identification on a daily or even weekly basis is simply unreasonable and impractical. The food and beverage processing industry spans a wide range of industrial operations, and many of these can include significant hazards to workers. In addition, positive identification of processes is required to maintain product quality. Common to almost all of these operations is the requirement of sanitation.
Typically food and beverage processes are run for two shifts out of three in a day, with the third shift reserved for cleaning and sanitation of the equipment. The cleaning is particularly harsh and includes exposures to high-pressure spray, scrubbing, caustic and acidic cleaning chemicals, and sanitizing chemicals. Usually this cleaning is done at elevated temperatures (e.g., 50° C. to 80° C. or even higher). This effort is needed to inhibit the growth of toxic bacteria which could otherwise compromise the efficacy of the end product.
Great efforts are made to be certain that cleanliness and hygiene is maintained. Equipment that is designed to sustain this exposure is required, and typically it comprises stainless steel as it can withstand the cleaning and presents a pore-free surface to minimize the ability of bacterial harborage. The cleaning process, designed to eliminate contaminants on the surface of equipment, makes it especially difficult for identification labels to remain in place. While mechanical attachment can withstand the washing forces and chemical exposures, it can also be compromised by the presence of crevices at attachment points that become a locus for bacterial harborage. Thus the use of a continuous adhesive is desirable for the attachment of signs and labels.
Signs and labels for industrial equipment that are commonplace in other industries are known to fail rapidly when exposed to the harsh conditions of the food and beverage processing operations. If the labels fail by falling off of the equipment to which it is attached, then the additional problem of product contamination can result. While it is common in this industry to use metal detectors to find potential contaminants from the process, these will not find plastic label materials.
What is clearly needed in this industry is the ability to label various process equipment with durable signage that can withstand the cleaning operations while maintaining legibility, and if attachment failure occurs, be readily detectable by process metal detection equipment.